Tagging is a feature that lets you record additional information on the items you save so that you can retrieve them more effectively in the future. Piggy Bank shows each item with a tag textbox where you can type several keywords (tags) separated by commas (see figure below).
As you type, Piggy Bank suggests previously used keywords that start with the same text you have typed so far. Hitting the Enter key will replace the text you type with the selected keyword in the dropdown list. You can use the up and down arrow keys to select another keyword before hitting Enter. Typing a comma or hitting Esc dismisses the dropdown list. When there is no dropdown list, hitting Enter causes the item to be saved and tagged with those keywords (the result is shown below).
Piggy Bank also lets you tag a web page with several keywords as a means to bookmark that page. To tag a web page, hit the backslash key \ or invoke the menu command Tools » Piggy Bank » Tag This Page. Piggy Bank will show a toolbar at the bottom of the window where you can type in keywords (see below).